With rapid development of communication technology, terminals have come to acquire increasingly powerful processing functions, and gained significant increase in storage capacity. Demands for data transmission between terminals are also growing. Take mobile phone terminals as example, current data transfer between two mobile phones is mainly achieved via electromagnetic waves (such as Bluetooth, and Wireless Fidelity (Wi-Fi)) and optical waves (such as infrared).
However, the prior solutions for data transmission between terminals have the following problems:    1. data transmission means, such as Bluetooth, Wi-Fi, infrared, etc., require a corresponding communication module to be added to a mobile terminal for supporting data communication.    2. both Bluetooth and Wi-Fi operate in the ISM (Industrial Scientific Medical) band, while the ISM band is an open band, and may be subject to interference from microwave ovens, cordless telephones, scientific research instruments, industrial equipment or medical equipment signals.    3. Wi-Fi requires simultaneous connection to the same AP (Wireless Access Point), whereas many mobile terminals do not support point-to-point connections.    4. some mobile phones do not support infrared transmission any more.
Therefore, a data transmission method is urgently demanded to solve the above problems.